The world is reassuringly stranger than we thought: another fanged frog has hopped into view, along with a leopard striped gecko, a tube nosed bat and a bird called the Nonggang babbler, all recently discovered in the Mekong delta in south-east Asia.

The announcement comes weeks after the revelation by a BBC team of their fanged frog, a different newly identified species, along with rats as big as cats, grunting fish and a teddy bear-like tree-climbing silky cuscus, all found on an expedition to a volcanic crater in Papua New Guinea.

The new bird-eating fanged frog, which lies in wait along the riverbank for prey including birds and large insects, is among a wealth of new species announced today by WWF International.

In 2008, scientists discovered 100 plants, 28 fish, 14 amphibians, two mammals and the new bird species in the region – on top of over 1,000 new species identified there in the previous decade.

Scientists believe the frog, found in eastern Thailand, and named Limnonectes megastomias, uses fangs as intimidating as any snake's in combat with other males, as well as to catch prey.

The leopard gecko, Goniurosaurus catbaensis, turned up on Cat Ba island in northern Vietnam. It has large beautiful cat-like eyes, and leopard stripes along the length of its body.

The scientist who found it, Lee Grismer from La Sierra University in California, said he was so engrossed in trying to capture it, it took his son to point out that his hand was resting on a rock inches away from the head of a pit viper.

"We caught the snake and the gecko, and they both proved to be new species," he said.

The bat was found in south-eastern Vietnam, and the Nonggang babbler bird in the rainforest on the border between China and Vietnam.

"After millennia in hiding, these species are now finally in the spotlight, and there are clearly more waiting to be discovered," said Stuart Chapman, director of the WWF Greater Mekong Programme.

He warned, however, that climate change, including floods and drought, threatened the survival of many of these species, just as the world learned of their existence.

"Some species will be able to adapt to climate change, many will not, potentially resulting in massive extinctions. Rare, endangered and endemic species like those newly discovered are especially vulnerable because climate change will further shrink their already restricted habitats."